萌新想用一元二次方程解题,然后洛谷IDE给了一个完全离谱的答案......
#include<bits/stdc++.h>
using namespace std;
long long k, n, e, d, q, a, b, c;
double x, y;
int main(){
scanf("%d", &k);
for(int i=1;i<=k;i++){
scanf("%d %d %d", &n, &d, &e);
printf("%d %d %d\t\t" , n, d, e);
a = 1;
b = e*d-n;
c = n;
if(b*b-4*a*c<0){
printf("NO\n"); continue;
}
/*
-b (+-) sqrt(pow(b, 2) - 4*a*c)
-------------------------------
2a
*/
//printf("%d %d %d\t\t\t", a, b, c);
//a=1; b=-2; c=1;
//printf("%d %d %d %d %d", pow(b, 2), pow(b, 2) - 4*a*c, sqrt(pow(b, 2) - 4*a*c), -b+sqrt(pow(b, 2) - 4*a*c), 1.0*(-b+sqrt(pow(b, 2) - 4*a*c))/(2*a));
x = 1.0*(-b+sqrt(pow(b, 2) - 4*a*c))/(2*a);
//printf("%d\n", x);
if(double(int(x)) == x){
y = n / int(x);
if(x>y) printf("%d %d\n", y, x);
else printf("%d %d\n", x, y);
continue;
}
printf("NO\n");
}
return 0;
}
输入:
10
770 77 5
633 1 211
545 1 499
683 3 227
858 3 257
723 37 13
572 26 11
867 17 17
829 3 263
528 4 109
标准输出:
2 385
NO
NO
NO
11 78
3 241
2 286
NO
NO
6 88
我的输出
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO